Quiet chargers

Quick charging stations from EBG compleo GmbH do more than just making the drivers of electric cars happy. Thanks to quiet fans, they also let their neighbors sleep soundly.

March 2017

Before the internal combustion engine was invented, it looked like the electric motor had a great future to look forward to; the first cars were powered by electricity and not gasoline. But then Carl Benz presented his Benz Patent Moorwagen on January 29, 1886. Soon after that, the combustion engine was considered superior to the electric motor. The batteries simply didn’t hold up long enough. In contrast, refilling with gasoline was fast and cheap.

But 130 years after Benz’s patent, electromobility is on the rise. It is expected to contribute to meeting ambitious worldwide climate targets. To make sure that electric vehicles can take their place on the roads, they will need better batteries that can be recharged faster.

“The only way to charge used to be the household electric socket. It could take half a day before the batteries were full.”

Kai Schönenberg, sales team leader at EBG compleo GmbH

In Lünen, a city in the German state of North Rhine-Westphalia, Kai Schönenberg is looking forward to this development. He is the sales team leader at EBG compleo GmbH, responsible for selling charging stations — the gas stations of the future. “We introduced our first charging station in 2009. Now there are almost 6,000 of our charging points in use throughout Europe,” says Schönenberg. Though it is still relatively new to the business, EBG compleo is now among the leaders in the sector. The company is a subsidiary of the EBG Group, which has been making distribution cabinets for over 60 years. The cabinets are designed for outdoor use and made of a special plastic that can withstand any weather. “In principle, charging stations are just outdoor power distributors. Since we already had the know-how, getting into this market seemed like the obvious thing to do,” says Schönenberg.

From socket to quick charger

The EBG Group

The company was founded in 1948 in Lünen, north of Dortmund. It specializes in the production of distribution cabinet housings. In 2009, the EBG Group entered the charging station business and founded EBG compleo GmbH for that purpose. The company develops and produces the charging stations and also offers service and maintenance packages. Customers include municipalities, electric utilities, car-sharing businesses and private companies such as banks.

Besides the range of a charged battery, the time it takes charge one is the main obstacle for acceptance of electric cars. “The only way to charge used to be the household electric socket, which can only deliver up to 3.7 kilowatts. It could take half a day before the batteries were full,” says Schönenberg. That’s no way to fill up quickly. The new CITO DC quick charging station is closing in on this target. It can completely recharge an empty battery with a capacity of 25 kilowatt-hours in about half an hour. “In practice, drivers only charge as much as they actually need. Then five to ten minutes of charging time is enough for the next few kilometers.”

But how does a charging station actually work ? In the company parking lot, Schönenberg points to a plain, slender pillar. “Many people wonder how it’s possible to pack so much performance into such a tight space,” he says, pointing to an unobtrusive cable distribution cabinet about twenty meters away. “We’ve separated the interface unit from the power unit. Otherwise the operators would have to post huge boxes weighing up to 500 kilograms by the side of the road.”

“Drivers need to be sure that the charging station will work. There’s no gas can for an electric vehicle.”

Kai Schönenberg, sales team leader at EBG compleo GmbH

Continuing with his demonstration, Schönenberg holds his customer card up to the charging station, pulls out the plug and inserts it into the socket in his company car. The charging process begins and Schönenberg walks over to the distribution cabinet. “When one or more vehicles are connected to the charging station, of course the power electronics generate a lot of heat that has to be dissipated efficiently. EBG compleo’s technology uses air cooling to prevent overheating. Drivers need to be sure that the charging station will work. There’s no gas can for an electric vehicle.”

Quiet neighborhood

The challenge during development was to develop a cooling system that didn’t need much space. So the engineers at EBG compleo chose two EC centrifugal fans from ebm-papst for their solution. “They’re not only compact and very reliable, they’re also extremely quiet. An important aspect since some charging stations are in residential areas,” says Schönenberg. The CITO is much quieter than required by noise abatement regulations. The fans can also be controlled as needed and only run when they are actually needed for cooling. “Our customers like the charging stations,” says Schönenberg and points to a couple of office containers. “We can’t build fast enough to keep up with our growth.”